4-Million-Year-Old Hominin Cranium Resembles That Of The Modern Human

Back in 1995, a 4-million-year-old hominin cranium was dubbed as the most ancient evidence of human evolution in South Africa. Now, more than 20 years later, scientists from the University of Witwatersrand, funded by the Center of Excellence in Palaeosciences, the Claude Leon Foundation, and the French Institute of South Africa, carried out complex high-resolution imaging of the cranium.

“The Jacovec cranium represents a unique opportunity to learn more about the biology and diversity of our ancestors and their relatives and, ultimately, about their evolution. Unfortunately, the cranium is highly fragmentary, and not much could be said about the identity nor the anatomy of the Jacovec specimen before,” said Dr. Amelie Beaudet from the University of Witwatersrand.

Now, helped by high-resolution imaging techniques, the scientists were able to observe fine details regarding the anatomy of the Jacovec specimen, an Australopithecus specimen. According to the study, the 4-million-year-old hominin cranium resembles that of the modern human.

The 4-million-year-old hominin cranium, belonging to an Australopithecus specimen, proved similar to that of modern human

“Our study revealed that the cranium of the Jacovec specimen and of the Australopithecus specimens from Sterkfontein, in general, was thick and essentially composed of spongy bone,” revealed Beaudet.

The same spongy bone structure is found in the modern human cranium, and its presence in the Jacovec specimen’s skull may suggest that Australopithecus hominins and modern day human share the same blood flow at the brain level.

On the other hand, when compared the 4-million-year-old hominin cranium’s high-resolution imaging results with the 2-million-year-old Paranthropus cranium, the scientists noticed a puzzling difference.

“We also found that the Paranthropus cranium was relatively thin and essentially composed of compact bone. This result is of particular interest, as it may suggest a different biology,” explained Beaudet.

According to the scientists, studying Australopithecus specimens could reveal new data about human evolution and, in this regard, the new high-resolution imaging techniques are constructive.